Temperature swing adsorption methods are known in the art for use in adsorptive separation of multi-component gas mixtures. Many conventional temperature swing adsorption processes are used for preferentially adsorbing one component of a feed gas mixture on an adsorbent material to separate it from the remaining feed gas components, and then subsequently to regenerate the adsorbent material to desorb the adsorbed component and allow for cyclic reuse of the adsorbent material. However, conventional temperature swing adsorption methods are typically limited in their efficiency due in part to limitations in the desorption or regeneration of the adsorbent material used in an adsorptive separation system, and also to limitations in the adsorption phase of the temperature swing adsorption process. Such inefficiencies in conventional temperature swing adsorption systems and methods have also led to inefficiencies in the integration of such systems into industrial systems where separation of gas mixtures may be desired, leading to undesirable costs in capital, energy and/or operating efficiency.
One type of industrial process where gas separation may be desirable includes combustion processes, where the separation of one or more gas component from a combustion process flue gas is required, such as for the removal and/or sequestration of carbon dioxide gas from fossil fuel combustion process flue gas mixtures, for example. In such applications, inefficiencies in conventional temperature swing adsorptive gas separation systems have typically led to undesireably inefficient integration of such temperature swing adsorptive gas separation systems into fossil fuel combustion processes, resulting in unacceptably high capital costs, reductions in energy efficiency and/or efficiency of gas separation, and operating costs, for example.
One inefficiency of typical conventional temperature adsorption processes in fossil fuel combustion applications is the inefficient adsorption of a desired combustion gas component on the adsorbent material, which may result from the rapid increase in temperature of the adsorption front when moving through the adsorbent material due to the heat of adsorption released as the gas component is adsorbed. In many conventional temperature swing adsorption methods, such increases in the temperature of the adsorbent material during adsorption may result in decreased adsorbent capacity associated with “hot spots” in the adsorbent material and a corresponding decrease in efficiency of the temperature swing adsorption process. Another shortcoming of typically conventional temperatures swing adsorption methods in fossil fuel combustion applications is the inefficient desorption or regeneration of the adsorbent material, which may result from the difficulty in uniformly heating the adsorbent material as thermal energy is required to meet the heat of desorption of the adsorbed compound during desorption or regeneration. Such non-uniformities in the heating of the adsorbent material may typically result in retained adsorption of a gas component associated with “cold spots” in the adsorbent material, or may require the application of an unnecessarily large thermal flux to sufficiently desorb the gas component, which may lead to undesirably high heating costs and leave the adsorbent material unnecessarily overheated following desorption, which undesirably affects continued adsorption system performance, and may typically require additional operating cost intensive remedies such as additional cooling steps in order to retain adsorptive functionality.